The Looney Tune shorts might fit in here. Characters like Bugs Bunny are entertaining to kids and adults, sometimes for different reasons.

The Three Stooges shorts might fit in here as well. Slapstick for the kids, but adults love it too.

and we can debate if the major part of the Disney library is for kids, or always built for the whole family in mind. I'm thinking especially of the live action films of the 1960s and 1970s like That Darn Cat, Hot Lead and Cold Feet, The Parent Trap, and Herbie the Love Bug

And some kids books have found large adult readerships, such as Treasure Island, Alice in Wonderland, and The Hobbit.

While Walt was alive they officially aimed for the whole family. After he died I'm not sure what they were trying to do. Arguably most "kid" flicks are also aiming for families, so it's ok to list them.

On Disney movie I enjoy is Blackbeard's Ghost. It's rarely mentioned, so I'll just throw it in here.

More kid movies:

Star Wars - They were aiming for a PG rating, which at the time was for teens, but that was only to attract older kids. Lucas once said he made it cause there was nothing on TV for kids to watch except cop shows.